It was 8.56am. Twenty-one passengers were dead or dying.
Evelyne Wade was in the carriage next to where she believed the bomb went off. Trembling and ashen-faced, she was amazed she had survived.
"We heard a big blast. The lights went out, and I thought I was going to die. Everyone was saying it was a fire and I thought we weren't going to get out alive," she said.
"We didn't move for 15 minutes and in that time, people were screaming, crying and banging on the windows, trying to get out. In the carriage next door, people were very injured and I saw a lot of blood on people."
Mrs Wade, 30, an estate agent from Oak Wood, said that when the train first juddered to a halt, she thought that it was just a continuation of delays that had already dogged her journey to work as an estate agent in Knightsbridge. But she soon realised it was more.
"We walked down the tunnel in the dark and there were a lot of injured people, and someone was dead. There was one big man who had lost all his clothes. There was someone else alive with no legs, we heard.
"There were lots of people in bandages and pads. We couldn't see very well because there was dust everywhere and people were panicking and covered in soot."
Rob Raimes was in the busy front carriage. "The lights suddenly went out and there was a crescendo of noise," he said. "Smoke had got in and was everywhere. My first instinct was that we had something on the track.
"We were in there for about 10 to 15 minutes until the driver let us out and we walked to the platform. It was a complete shock. One minute you are travelling to work as usual and then I thought I was going to die."
Mr Raimes, 44, a lawyer from Finsbury Park, north London, stayed for nearly two hours after he reached the platform at King's Cross, helping others who had escaped the blast.
"It was very distressing for me and I saw people who were badly injured. I didn't see any fatalities but I saw some who had lost part of their limbs and cut-glass injuries. There were quite a lot of people who helped, including passers-by."
Another passenger, Luiza Petterson, 36, a projects assistant in an engineering firm, said of the blast: "It felt like it was in our carriage but it have been anywhere. The lights went off and smoke came straight away, black smoke - you couldn't see anything. Everything was just pitch dark. You couldn't breathe. Everybody was coughing.
"A few people were panicking, but people in our carriage were very good. We made a decision to find a sharp object and smash the windows because the doors were stuck.
"Whether it was the right thing to do or not, ,we just climbed out and made our way towards the platform. It was smoky in the tunnel but as we walked down it became a bit clearer so at least we could breathe.
"We came to where there was another tunnel. We didn't know whether another train would be coming but we made a decision to go.
"We were some of the first people to get out. The station [King's Cross] was closed and there were people giving us water. We were happy to get out."
Other passengers were trapped inside the train for much longer. One, who declined to be named, said it was at least half an hour before she was evacuated from the back of the train, which lay about 50 metres from the platform at King's Cross.
"There was lots of panic and lots of head injuries," she said. "I thought one woman had lost an eye."
The streets around King's Cross filled with passengers who had been hurriedly evacuated as the scale of the emergency became clear. They dragged suitcases and checked maps to try to work out where to head next.
Those who had been caught up in the explosion, and evacuated both through King's Cross the Russell Square station, were readily identified by their smoke-streaked faces and dazed air.
Cordon after cordon of police tape was thrown up, trapping buses and cars in a rush-hour limbo, as officers tried to assess the situation, which grew only more tense as the bus exploded a few streets away in Tavistock Square.
For hours, convoys of ambulances with lights blazing took the injured to the University College Hospital and The Royal Free Hospital in Hampstead. Emergency treatment centres for the walking wounded were established in the hotels around King's Cross.
Helicopters hovered overhead adding to the sense of a national emergency while increasing numbers of those caught up in the crisis gathered in pubs and cafes to watch the rolling news headlines.
Others just stood open-mouthed with disbelief on the streets, blocked in by the cordons, unable to get to work or to head for home, just watching the passing blood transfusion vans and police checking the streets with sniffer dogs.
In the wake of 11 September, many Londoners had worried that the city would follow New York in becoming a terrorist target but the fears had diminished as time passed.
Mr Raimes said that he had expected this to happen years ago. "Compared to a couple of years ago, my radar was turned off," he said.
'I heard screaming... people were trying to get out'
Eamon Spelman, 47, a carpet dealer from Bounds Green in north London, was on the King's Cross train. He said: "After the huge bang and flash of light there was a deadly silence and then people in the next carriage started panicking and I heard a lot of screaming. People got their hankies out and covered their mouths so the dust would not affect them. The emergency lights came on so it was not pitch black.
Lots of people were crying and the lady next to me kept talking about her two children. Some people were trying to break the windows to get out. I was trying to calm them down and told them not to break the windows because there was thick, grey-back smoke outside and I thought the line might still be live.
The overcrowding in the carriage may have saved everyone because no one could fall over.
People from the fifth carriage had broken the glass from their windows and were walking on the track. Communication from the driver had stopped and it was 20 minutes before we saw a London Transport guy and then my major concern was that there was a fire.
When I got out and saw some of the other passengers, I was shocked. There were a lot of people with head injuries and blood running down their faces. We were all just relieved to be alive."
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